Turn-down incandescent lamp.



No'. 800,993. PATENTED OCT. 3, 1905. S. E. DUANE.

TURN DOWN INGANDBSGENT LAMP.

APPLICATION Hum NOV 15 1904 UNITED STATES PATENT OFFICE.

SAMUEL EVERETT DOANE, OF CLEVELAND, OHIO, ASSIGNOR TO THE NATIONALELECTRIC LAMP COMPANY, OF CLEVELAND, OHIO, A

CORPORATION OF NEW JERSEY.

TURN-DOWN INCANDESCENT LAMP.

Specification of Letters Patent.

Patented Oct. 3, 1905.

Application filed November 16, 1904! Serial No. 232,931.

To (0 wit/mt "it vnay concern:

Be it known that I, SAMUEL EVERETT DOANE, residing at Cleveland, in thecounty of Cuyahoga and State of Ohio, have invented a certain new anduseful Improvement in Turn- Down Incandescent Lamps, of which thefollowing is a full, clear, and exact description, reference being hadto the accompanying" drawings.

Incandescent electric lamps having two filaments and a switch on thebase of the lamp arranged to differently connect the-filaments, wherebythe candle-power of the lamp may be varied, are in common use under thename of turn-down lamps. A convenient arrangement of such lamps hasbeento have the switch operated by a pair of cords, one of which is pulledto cause the illumination of the bright filament and the other the dimfilament. This arrangement has been found satisfactory, except thatwhere the lamps are placed within ordinary reach it frequently happensthat one inadvertently takes hold of or touches the switch itself,receiving an unpleasant or dangerous shock.

The object of the present invention is to eliminate the possibility ofsuch contact. This I accomplish by providing a protecting-cap which ispreferably made of insulating material and is so formed that it snuglygrasps the base of the lamp and covers over the switch withoutinterfering with the operation thereof. The peculiar form of the cap bywhich it accomplishes this result in an efi ective manner while beingneat in appearance is comprehended within the present invention and ishereinafter more fully explained, and definitely set out in the claims.

The drawings clearly illustrate my invention.

Figure 1 is a side elevation of a turn-down lamp in place in its socketand having my shielding-cap. Fig. 2 is a similar view sectioned throughthe cap. This View, as far as the cap and switch are concerned, is takenfrom the same point of view as Fig. -1. The

filaments, however, are shown as from a position at right angles toFig. 1. The remaining figures are views of the cap itself, Fig. 3 beinga top plan, Fig. 4 being a bottom plan, and Fig. 5 a cross-section onthe line 5 5 of Fig. 4:.

Referring to the parts by letters, A represents the globe of the lamp,and B the usual cap forming the'base thereof. This base has some usualmeans for engaging the socket C and has also a cylindrical portion 6,which carries the switch. In the form shown the movable part of theswitch consists of a plate D, pivoted to the cylindrical portion 6 ofthe base. This plate has a pair of cars (Z, through which pass theoperating-cords E E, these cords being guided through suitable eyes Z),attached to the base. The switch member D is adapted to make contactwith either of a pair of insulated pieces F, which are set into the baseand are connected one for the ordinary filament Cr and the other for thedim filament G. Thus when one cord is pulled the bright filament isilluminated; when the other cord is pulled, the dim filament. Thisconstruction of switch is a well-known form and is to be taken as anillustration of any switch formed on the projecting portion of the baseof the lamp.

The insulating-cap by which I shield the switch is designated H. It hasthe following peculiar formation: There is a partly cylindrical wall inextending for something over half a circumference and adapted to snuglyembrace the base portion Z). This wall hasoutwardly-extending portionsit h, between which is a connecting portion if, which is a portion of acylinder of larger radius than the portion it, concentric therewith.Extending inward from the'upper edge of the wall It is a flange if, andextending inward from the walls it and b is a wider flange if, whichmerges with the flange 72 these two flanges being in the same plane andbounding a circular hole 71 The hole it of the cap is of substantiallythe same diameter as the exterior of the lampbase above the cylindricalportion b. The walls are located just a little farther apart than theeyes 5 on the base, and the offsetwall 72/ is just far enough out fromthe base to loosely cover the switch, clearing the ears (Z. The wall Ithugs the base portion bof the lamp snugly enough to retain the cap inplace. Moreover, when the lamp is in its socket the inwardly-extendingflanges 71/3 and it" of the cap are restrained between the end of thesocket and a shoulder on the base. The walls of the cap extend downwardbeyond the base portion, as shown.

It will be seen from the illustration and description that the cap isunobtrusive, may be easily removed when the lamp is removed from thesocket, but is securely held in place when the lamp is in the socket,and thus effectively prevents accidental contact with the switch withoutinterfering with its operation or with the appearance of the lamp.

I claim 1. The combination with a turn-down incandescent lamp having ametal base composed of a threaded portion adapted to engage in a socket,and a plain portion above said threaded portion, a switch mounted on theoutside of said plain portion, and a protecting-cap embracing the plainportion of said base and extending over said switch.

2. The combination of a turn-down incandescent lamp, having a metallicbase, an external switch on said base and an insulatingcap fitted uponsaid base and having an offset portion which shields the switch.

3. The combination of a turn-down incandescent lamp, having a metallicbase, the socket for said base, a switch upon said base outside of saidsocket, and a protecting-cap held between said base and said socket andextended over said switch.

4.. A protecting-cap for the base of a turndown incandescent lamp havinga switch upon its base, said cap having an opening for receiving thethreaded portion of said base, and an offset portion adapted to extendover said switch and shield the same.

5. The combination of an incandescent lamp having an exterior switch onits base, a pro tecting-cap adapted to snugly embrace such base, andhaving an offset portion to cover the switch and an inwardly-extendingflange to engage a shoulder on the base.

6. The combination of an incandescent electric lamp havinga base with acylindrical portion, a switch mounted on the exterior of suchcylindrical portion, an insulating-cap having a partly-cylindrical walladapted to embrace the cylindrical portion of the base and having shortoutwardly-extending walls and having a second wall connecting said shortwalls and far enough out to clear the switch.

7. The combination of an incandescent electric lamp having a base with acylindrical portion and a switch mounted on the exterior of suchcylindrical portion, with a protectingcap having a partly-cylindricalwall adapted to embrace the cylindrical portion of the base, and havingan outwardly-offset wall loosely covering the switch, andinwardly-extending flanges from such walls bounding a circular hole,whcreby the cap shields the switch and is held in place by embracing thecylindrical wall of the base and by extending over a shoulder thereon.

8. The combination of an incandescent electric lamp, having a base witha cylindrical portion, a switch mounted on the exterior of suchcylindrical portion, an insulating-cap having a partly-cylindrical walladapted to embrace the cylindrical portion of the base. and having shortoutwardly-cxtending walls connected by a partly-0ylindrical wall, makingan oifset portion far enough out to clear the switch, inwardly-extendingflanges from all of said walls, merging ina common plane and bounding acircular hole. the recess bounded by the offset portion of the cap beingopen toward the globe of the lamp. and cords for operating the switchpassing therefrom through such opening.

In testimony whereof I hereunto allix my signature in the presence oftwo witnesses.

SAMUEL RETT DOA NE.

YVitnesses:

H. S. BLAoK. E. B. GILCHRIsT.

